Air pollution levels are currently 'very high' across parts of England, particularly London and the east.
Three of the Department for Environment, Food & Rural Affairs (DEFRA's) pollution monitoring devices in London showed a maximum '10' reading for airborne pollution today. The sites were at London North Kensington, Camden Kerbside and on the Marylebone Road. At level 10, advice from DEFRA is that adults and children with lung or heart problems should avoid strenuous physical activity, while asthmatics may need to use their inhaler more often.
Yesterday, when parts of London reached level 10 for air pollution, London's Mayor, Sadiq Khan tweeted "The shameful state of London's toxic air today has triggered a 'very high' air pollution alert under my new air quality warning system." Data from London's main monitoring system showed that a site on Brixton Road, south London broke the annual limit for nitrogen dioxide pollution just five days into 2017.
Other sites across London and eastern England were seeing levels of 8 and 9, with Southend-on-Sea and Norwich scoring an '8'. In total, DEFRA has 5,000 monitoring stations across the UK.
Five pollutants monitored by DEFRA's equipment are ozone, nitrogen dioxide, sulphur dioxide, and the particulates PM2.5 and PM10. PM2.5 are particles in the air less than 2.5 microns (0.0025mm) in diameter, while PM10 are particles up to 10 microns in diameter. Both kinds of particles can get into the lungs and potentially cause health problems. In cities, the main reason for high levels of air pollution is road traffic. Diesel vehicles produce more pollutants than petrol cars, but both contribute to the problem. Air pollution levels have been unusually high in parts of London and eastern England in recent days because of high atmospheric pressure and light winds.
Low emission and electric vehicles will play a big part in reducing air pollution levels in the future.
Photo by David Holt